1. Field
The present application relates in certain embodiments to prosthetic and orthotic devices. In particular, the present application in certain embodiments relates to prosthetic and orthotic device with one or more magnetorheological (MR) elastomer springs having a controllable stiffness.
2. Description of the Related Art
Conventional prosthetic and orthotic devices seek to approximate the feel and fluid range of motion of a human limb's natural movement, such as the natural stride of a human foot. Additionally, prosthetic and orthotic devices seek to provide the appropriate level of stiffness for the user, based on the activity level of the user. High stiffness is required in more demanding activities (e.g., running, jumping), while low stiffness is required for comfort while at rest or moving casually (e.g., walking). However, the components in conventional orthotic and prosthetic devices (e.g., prosthetic foot plates and heel plates) generally have a set or fixed stiffness, regardless of the activity level of the user.
Accordingly, there is a need for orthotic and prosthetic devices where the stiffness of the device is controllable and adaptable to the user's activity level, and capable of being controlled either manually or automatically by responding to signals that represent the current activity level of the user, where the operating characteristics of the device can be changed in real-time.